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排序方式: 共有10000条查询结果,搜索用时 17 毫秒
991.
Conrad P. Quinn Carol L. Sabourin Nancy A. Niemuth Han Li Vera A. Semenova Thomas L. Rudge Heather J. Mayfield Jarad Schiffer Robert S. Mittler Chris C. Ibegbu Jens Wrammert Rafi Ahmed April M. Brys Robert E. Hunt Denyse Levesque James E. Estep Roy E. Barnewall David M. Robinson Brian D. Plikaytis Nina Marano 《Clinical and Vaccine Immunology : CVI》2012,19(11):1730-1745
A 3-dose (0, 1, and 6 months) intramuscular (3-IM) priming series of a human dose (HuAVA) and dilutions of up to 1:10 of anthrax vaccine adsorbed (AVA) provided statistically significant levels of protection (60 to 100%) against inhalation anthrax for up to 4 years in rhesus macaques. Serum anti-protective antigen (anti-PA) IgG and lethal toxin neutralization activity (TNA) were detectable following a single injection of HuAVA or 1:5 AVA or following two injections of diluted vaccine (1:10, 1:20, or 1:40 AVA). Anti-PA and TNA were highly correlated (overall r2 = 0.89 for log10-transformed data). Peak responses were seen at 6.5 months. In general, with the exception of animals receiving 1:40 AVA, serum anti-PA and TNA responses remained significantly above control levels at 28.5 months (the last time point measured for 1:20 AVA), and through 50.5 months for the HuAVA and 1:5 and 1:10 AVA groups (P < 0.05). PA-specific gamma interferon (IFN-γ) and interleukin-4 (IL-4) CD4+ cell frequencies and T cell stimulation indices were sustained through 50.5 months (the last time point measured). PA-specific memory B cell frequencies were highly variable but, in general, were detectable in peripheral blood mononuclear cells (PBMC) by 2 months, were significantly above control levels by 7 months, and remained detectable in the HuAVA and 1:5 and 1:20 AVA groups through 42 months (the last time point measured). HuAVA and diluted AVA elicited a combined Th1/Th2 response and robust immunological priming, with sustained production of high-avidity PA-specific functional antibody, long-term immune cell competence, and immunological memory (30 months for 1:20 AVA and 52 months for 1:10 AVA). Vaccinated animals surviving inhalation anthrax developed high-magnitude anamnestic anti-PA IgG and TNA responses. 相似文献
992.
993.
Atherosclerotic cardiovascular disease is a prevalent human disorder and a significant cause of human morbidity and mortality. A number of risk factors may predispose an individual to developing atherosclerosis, and of these factors, cigarette smoking is strongly associated with the development of cardiovascular disease. Current thinking suggests that exposure to toxicants found in cigarette smoke may be responsible for this elevated disease likelihood, and this gives rise to the idea that reductions in the levels of some smoke toxicants may reduce the harm associated with cigarette smoking. To assess the disease risk of individuals who smoke cigarettes with altered toxicant levels, a weight-of-evidence approach is required examining both exposure and disease-related endpoints. A key element of such an assessment framework are data derived from the use of in vitro models of cardiovascular disease, which when considered alongside other forms of data (e.g. from clinical studies) may support evidence of potential reduced risk. Importantly, such models may also be used to provide mechanistic insight into the effects of smoking and of smoke toxicant exposure in cardiovascular disease development. In this review the use of in vitro models of cardiovascular disease and one of the contributory factors, oxidative stress, is discussed in the context of assessing the risk potential of both conventional and modified cigarettes. Practical issues concerning the use of these models for cardiovascular disease understanding and risk assessment are highlighted and areas of development necessary to enhance the power and predictive capacity of in vitro disease models in risk assessment are discussed. 相似文献
994.
995.
Brian W. Booth 《Growth factors (Chur, Switzerland)》2013,31(4):227-235
Transforming growth factor-alpha (TGFα) is a member of the epidermal growth factor (EGF) family. Expression of TGFα is highly regulated in response to exogenous cellular signals including cytokines and other growth factors. The growth factor has been found to be indispensable for proper development of many tissues and organs. TGFα has also been implicated in numerous disease states including forms of breast cancer. This minireview summarizes the basic biology of TGFα and its actions during normal and pathogenic development of the mammary epithelium. 相似文献
996.
997.
Anthony J. Little Alison E. Seline Brian L. Swick Karolyn A. Wanat 《Journal of cutaneous pathology》2016,43(8):684-687
Adenoid cystic carcinoma (ACC) is a tumor that can be of primary cutaneous origin or secondary to metastatic disease, most commonly salivary origin. Aside from primary cutaneous and salivary types, ACC of the breast is a rare, more indolent variant. Cutaneous metastases secondary to breast ACC is exceedingly uncommon and not previously reported to our knowledge. We present the case of a 67‐year‐old woman who developed cutaneous metastasis from primary breast ACC. 相似文献
998.
Brian K. Heimbuch William H. Wallace Charles L. Balzli Michelle L. Laning Delbert A. Harnish 《Journal of occupational and environmental hygiene》2016,13(2):D11-D15
Nosocomial infections pose a significant and escalating threat to both patients and healthcare workers (HCWs). By their nature, hospitals induce antibiotic resistance in virulent and commensal strains, leading to increasingly severe hospital-acquired infections. This study measured environmental exposure experienced by domestic staff cleaning vacated patient rooms of a community hospital to bacteria in ambient bioaerosols. While they cleaned the room, participants wore an N95 filtering facepiece respirator (FFR), from which coupons were cut and bacteria were extracted, cultured and enumerated. Extrapolation to the full area of the respirator yielded measured exposures of 0.2–1.4 × 104 colony-forming units/hour, of which ~97% collected on the front layer of the N95, suggesting a possible role for minimal respiratory protection in nonpatient environments. Random resistance testing of 1.6% of the isolates showed that ~70% of both Gram-positive and Gram-negative organisms exhibited resistance to oxacillin and ~9% of the Gram-positives displayed resistance to vancomycin. These data provide an estimate for mask bioaerosol loading that can be used in risk modeling and to refine strategies for reuse of FFRs during critical shortages. 相似文献
999.
Tumour‐associated mast cells in classical Hodgkin's lymphoma: correlation with histological subtype,other tumour‐infiltrating inflammatory cell subsets and outcome 下载免费PDF全文
Patricia S. Nielsen Knud Bendix Rikke Riber‐Hansen Torben Steiniche Stephen Hamilton‐Dutoit Michael Clausen Francesco d'Amore 《European journal of haematology》2016,96(3):252-259
The tumour microenvironment in classical Hodgkin's lymphoma (cHL) is characterised by a minor population of neoplastic Hodgkin and Reed–Sternberg cells within a heterogeneous background of non‐neoplastic bystanders cells, including mast cells. The number of infiltrating mast cells in cHL has been reported to correlate with poor prognosis. We used immunohistochemistry to assess the degree of tumour‐infiltrating mast cells in cHL tissue microarrays and correlated this with clinico‐pathological features and prognosis in a cohort of homogeneously treated patients with Hodgkin's disease. A high degree of tumour mast cells was associated with nodular sclerosis (NS) subtype histology (P = 0.0002). Moreover, the number of mast cells was inversely correlated with the numbers of CD68+ and CD163+ macrophages (P = 0.0001 and P = 0.003, respectively) and with the number of granzyme+ cytotoxic cells (P = 0.004). The degree of mast cell infiltration was not a prognostic factor in cHL of nodular sclerosis subtype. In contrast, in mixed cellularity cHL a high number of intratumoral mast cells correlated with significantly poorer outcome both in terms of overall (P = 0.03) and event‐free survival (P = 0.01). Further studies are warranted into the biological mechanisms underlying this adverse outcome and their possible therapeutic implications. 相似文献
1000.
Sandra Ovesen Karina Frahm Kirk Hans Linde Nielsen Henrik Nielsen 《APMIS : acta pathologica, microbiologica, et immunologica Scandinavica》2017,125(3):230-235
Campylobacter concisus is an emerging pathogen associated with gastrointestinal disorders such as gastroenteritis and inflammatory bowel diseases (IBD), but the species is also found in healthy subjects. The heterogeneous genome of C. concisus increases the likelihood of varying virulence between strains. Flagella motility is a crucial virulence factor for the well‐recognized Campylobacter jejuni; therefore, this study aimed to analyze the motility of C. concisus isolated from saliva, gut biopsies, and feces of patients with IBD, gastroenteritis, and healthy subjects. The motility zones of 63 isolates from 52 patients were measured after microaerobic growth in soft‐agar plates for 72 hours. The motility of C. concisus was significantly lower than that of Campylobacter jejuni and Campylobacter fetus subsp. fetus. The motility of C. concisus varied between isolates (4–22 mm), but there was no statistical significant difference between isolates from IBD patients and healthy subjects (p = 0.14). A tendency of a larger motility zones was observed for IBD gut mucosa isolates, although it did not reach statistical significance (p = 0.13), and no difference was found between oral or fecal isolates between groups. In conclusion, the varying motility of C. concisus could not be related to disease outcome or colonization sites. 相似文献